Passenger jets have been chartered, military airwaves cleared and the beer and pizza supplies checked. The London 2012 summer Olympics is poised to become the biggest media and broadcasting event in history with an invasion of commentators, celebrity anchors, reporters, technicians, makeup artists, camera and sound operators from 190 countries.

Starting on 27 June when the main press centre opens its doors, the Games organisers are expecting up to 28,000 members of the media to descend on London – almost three times more than the number of athletes competing. America's NBC TV network is sending 2,700 people, enough to warrant the charter of three Boeing 777 aircraft to help get them in and out. The broadcast centre where most of them will work is big enough to park those three jets with room for at least two more jumbos, while the main press centre is the size of the Tate Modern gallery. It will be broadcasting and publishing on an unprecedented industrial scale, fuelled by London's international allure.

"London is such a desirable location and you have a number of athletes who have pointed to the event as being the pinnacle of their careers," said Darryl Seibel, the British Olympic Association's director of communications. "Usain Bolt has very much geared his four-year programme to this moment. Plus it is one of the world's great cities and sport is a significant part of the culture."

The BBC is planning 2,500 hours of live action produced by a staff of 765 while al-Jazeera, the Qatar-based network that broadcasts mostly to the Middle East and North Africa, is sending 150 staff to broadcast in Arabic and English. Every vantage point around the main stadium has been grabbed for use. The BBC and al-Jazeera have commandeered the top floors of apartment blocks in Stratford to build studios. NBC will broadcast in English and Spanish and if you tried to watch every hour of its planned coverage without a break, it would take until next February.

The International Olympic Committee has accredited journalists from 28 more countries than at the Beijing Games – among those sending at least one reporter are nations few have even heard of. They include Kiribati, a string of atolls in the Pacific with a population of around 100,000 and the even smaller Nauru, a phosphate rock island in Micronesia that has a population put at only 10,000. Journalists are also coming from Somalia and Afghanistan, Barbados and Belize in the Caribbean, Liechtenstein and Andorra in Europe and Lesotho, Togo and Malawi in Africa.

The centre of all this attention is the main press centre, or "bull pen", on the north-western edge of the Olympic park in east London. It is a vast hangar of work benches over which are suspended 260-cm TV screens. It will be home to many of the 5,800 fully accredited press who have access to all the events, half from the UK and the rest of Europe, just over 2,000 from the Americas and Asia, 220 from the Oceania region and 150 from Africa. Many will hardly leave a facility that has been designed as a 24-hour production line of sports news. Medallists will be shuttled from their venues to deliver reaction in one of the press conference theatres – the largest of which has room for 700 reporters. At peak times, there will be 24 press conferences a day. Veterans predict it will be exhilarating but exhausting and organisers will be on the lookout to prevent frazzled reporters setting up camp under their desks(see below).

"One of the quietest places at an Olympic Games is a media shuttle bus from the main press centre to a competition venue," said Seibel, who has worked on press relations for US and UK Olympic authorities at eight Games stretching back to Barcelona in 1992. "It's where the unofficial, but highly popular Olympic event of bus-napping occurs. Journalists work extraordinarily hard during the Games. It's long hours and often extreme pressure. Finding 15 minutes to grab a nap can be pure bliss."

Said Mandy Keegan, the press centre's operations manager: "In terms of home comforts, we have built a high street for the media, which not only contains a pharmacist and technology shop but also a massage centre and a fully kitted-out health centre staffed by doctors and nurses." Her team have found time to calculate they are going to serve up 6.5 miles of spaghetti and 26,700 cucumbers. Freshly baked pizza and cold beer will be delivered to desks for reporters working late between 11pm and 4am. For diversion there's a gym, a prayer room and, of course, a bar.

It is little surprise so much attention is being paid to the fourth estate. The Olympic movement relies on international TV audiences for its income and earned a reported £2.7bn from the sale of TV rights for London 2012 and the winter Olympics in Vancouver in 2010.

"We recognise the media are massively important stakeholders in the games," Andy Hunt, chief executive of the British Olympic Association told an audience of accredited British journalists this month. "We are totally committed to you having a successful Games."

But the news list will not be entirely dominated by reports of world-record performances and quotes from pumped-up medallists. Riots and terror attacks are already on the agenda, according to the Locog press office, which is now receiving 2,000 calls a week.

"They are the obvious questions to ask," said Locog's head of PR and media, Joanna Manning-Cooper. "We ran a beach volleyball test event on the Tuesday of the week the riots took place [last August] and people remember that the 7/7 attacks on London came the day after the bid win."

A selection of headlines from Press TV, the Iranian government-backed English-language channel this month, hints at the channel's approach. A story about tourism numbers was headlined: "Olympic economic hopes go up in smoke"; while another reported on "the wave of Islamophobia which the British government has apparently unleashed on Muslims ahead of the 2012 Olympic games".

Russia Today, the Kremlin-funded multilingual TV news service, will send a team of 15 correspondents and crew for its English, Spanish and Arabic channels.

Tatyana Chistikova, a spokeswoman for the Moscow-based channel said that as well as covering the sport, they will also report on "how hosting the Olympics has affected the life in London; experiences of the fans and the visitors, and what, if any, effect do the Games have on the precarious economic and political mood that has struck the UK and Europe in recent months".

The Locog chairman, Lord Coe, has been on an international charm offensive. Since December, he has travelled to China, Japan, the US, Brazil, Tanzania, Morocco, France, Spain, Sweden, Germany and Russia.

The PR opportunity presented by so many journalists gathered in one place will be grasped more widely, too. Thousands of unaccredited journalists are coming to cover the Games without access to the venues and that presents a huge opportunity for PR executives with a product, a city or a country to promote. National "hospitality houses" are being set up all over the capital, with African countries coming together in Kensington Gardens, the "Casa Brasil" at Somerset House, Russia Park next to Kensington Palace and the French "Olympic village" at Old Billingsgate Market. The most established is Holland House, sponsored by Heineken, which will be based in Alexandra Palace, north London.

A further 6,000 members of the media have signed up for access to the London tourist board's facility near Trafalgar Square, which is aimed at selling London and the UK to the rest of the world.